Hydraulic elevator



(No Model.)

J. G; STAMP.

HYDRAULIC ELEVATOR. No. 459,209.. Patented Sept. 8, 1891.

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Srar'ss PATENT OFFICE.

.HYDRAU LlC ELEVATOR.

SPECIFICATION forming part of Letters Patent No. 459,209, dated September 8; 1891,

Application filed June 22, 1891.

To all whom it may concern.-

Be it known that I, JOHN G. STAMP, a citizen of the United States, residing at Buffalo, in the county of Erie and State of New York, haveinvented new and useful Improvements in Hydraulic Elevators, of which the following is a specification.

This invention relates to the pumping apparatus which is employed in connection with hydraulic elevators for supplying water un der pressure to the cylinder, whereby the system of pulleys and lifting-cables of the elevator-car are actuated. The compressed air escapes in small quantities with the water discharged from the pressure chamber containingthe compressed air and water, so that in time the volume of compressed air be comes so small that its expansive force is insuihcient to operate .the elevator. In order to discharge the excess of water and permit the proper volume of air to be restored to the pressure-chamber, it has been customary to rm'r the elevator-car up and down empty; but this requires considerable time and causes delays. It has hitherto been sought to overcome this difficulty by connecting an air-pipe with the suction-chamber of the pump, so as to mix the water with the air before its delivery into the pressure-chamber, and thus replace the loss of air; but unless the air sup plied to the pump is properly regulated the volume of air so drawn into the pump-cylinder will be excessive, in which case the air acts as a cushion, which impairs the action of the pump and sometimes requires the pump to be stopped to allow the air to escape, causing annoying interruptions of the elevator service.

The object of my invention is to so organize the pumping apparatus that when the volume of compressed air in the pressure-chambcr becomes deficient from any cause the proper quantity of air may be readily restoredwithout regulating the water-supply to the pump or requiring the elevator to be. run empty to discharge the surplus water from the pressure-chamber.

In the accompanying drawings, Figure 1 represents a sectional elevation of ahydraulicelevator plant embodyin; my improvement.

8.5.1 N01 397.059. (No model.)

Fig. 2 is a vertical section of'tlie'air-injector on an enlarged scale. Fig. 3 is a cross-see tion in line a; :r, Fig. 2.

Like letters of reference refer to like parts in the several figures. I V

A represents the closed pressure-chamber containing water and'compressed air, and A is the pipe whereby the water is delivered under pressure from the chamber A to the usual' actuating-cylinder of the chamber.

This actuating-cylinder and the system of pulleys and lifting-cables operated by the same are not shown in the drawings, and may be of any ordinary construction. V B is the pump, and b the pipe, throng which water is delivered by'the pumpinto the lower portion of the pressure-chamber A. (J is an open water-tank, from which the pump draws its supplythrough the suctionpipe D. The latter may be provided with a valve d for shutting Y off the-supplyof water to the pump for making repairs'or'for other purposes. v

E is an auxiliary pipeleading from the pressure-tank A to the suction-pipe'D. This aux iliary pipe enters the pressure-chamber below the water-level, and is provided with a cut-elf valve e.

F is an air-injector connected with the'auxiliary pipe E, and whereby air is commingled. with the water flowing through said pipe. This air-injector consists, preferably, of a pipe 'f, which enters a shell crossing 8', arranged in the auxiliary pipe E, and extends downwardly a short distance into the upright portion of the latter, the pipe f being separated from the surrounding water-pipe by an annular space, through whichthe water passes. The injector-pipe f is provided with a depending branch' f having a valve f 2 for rcgu= lating the quantity of air admitted to the injector. Upon opening the valve c of the auxiliary pipe E and the valve f of the injector the water passes through the pipe E into the supply-pipe of the pump, producing a vacuum at the mouth of the injector-pipe f, whereby air is drawn into the auxiliary pipe and mixed with the water supplied to the pump. A perforated diaphragm f 3 is preferably arranged in the pipe E at the mouth of the injector-pipe f to restrict the passage of the water at this point and increase the force of the suction.

In the ordinary operation of the apparatus the valve of the suction-pipe 7) is wide open and the valves of the injector-pipe f and the auxiliary pipe E are closed, so that the water in the pressure-chamber A is shut off from the pipe E and the injector rendered inoperative. When the volume of air in the pressurechamber becomes deficient, the valve of the auxiliary pipe E and the regulating-valve of the injector-pipe are opened. 'Aportion of the water in the pressure-chamber is now forced into the pipe E and in its passage through the same is mixed with air. The water charged with air is delivered into the suction-pipe D of the pump and, forced by the latter into the pressurechamber,

whereby the volume of air in the latter is increased, the air rising above the surface of the water into the air-space in the upper part of the chamber. As the water for operating the air-injector is drawn from the pressurechamber; the latter is gradually relieved of its surplus water, and the water so discharged is replaced by the air and partly by the water forced into the chamber. When the proper proportion of vwater and air is established in the pressiu-e-chamber, the valves of the auxiliary pipe E and injector F areclosed. The

proper volume of air is thusreadily restored in the pressure-chamber, when necessary, without requiring the elevator to be run up and down numerous times, and as the flow of the water to the pump is unrestricted the pump always has a sufficient supply to prevent air from being delivered into the pump in such large quantities 'as to cushion the pump and impair its action.

It is obvious that any othersuitable air-injecting devicemay be employed instead of that described and shown.

I claim as my invention 1. In a hydraulic elevator, the combination, with a pressure-chamber containing air and water and a pump for delivering water to said chamber, of a suction-pipe connecting the pump with the source of supply, an auxiliary pipe leading from the pressure-cylinder to said suction-pipe, and an air-injector arranged in said auxiliary pipe, whereby the water in the latter is mixed with air, substantially as set forth. I

2. In a hydraulic elevator, the combination, with a pressure-chamber containing air and water and a pump having its deliverypipe connected with the pressure-chamber, of a suction-pipe connecting the pump with the source of supply, an auxiliary pipe connecting said suction-pipe, with the pressure-cylinder and having a cut-off valve, and an airinjector arranged in said auxiliary pipe and provided with a valve for regulating the supplyof air to the injector,substantially as set fortln Witness my hand this 15th day of June, 1891.

- 7 JOHN G. STAMP. \Vitnesses:

C. F. Gavan, FRED. (.1. GEYER. 

